Microdermabrasion (xe2x80x9cMDAxe2x80x9d) is a term to describe the use of an air stream with entrained small particles such as aluminum oxide or hydroxide to impinge on to the stratum corneum or top layer of skin.
The devices used to deliver the stream of particles are varied. Positive pressure or grit blasting devices are composed of a compressor, grit or abrasive reservoir through which the air stream from the compressor passes in a confined space, to a nozzle placed near the skin. There is an obvious problem with abrasive and tissue debris not being easily confined by this technique. In compressor assisted systems, a compressor is connected to the mixing bottle and when the compressor is activated, air is pushed through the mixing bottle, and outputs a stream of air with entrained particles to the handpiece. One such prior art device is shown in U.S. Pat. No. 5,810,842, hereby incorporated by reference. In this device, the compressor is activated by a footswitch. The use of a footswitch is considered a drawback, as the operator requires good eye/foot coordination to effectively control the compressor and the resulting stream of particles through the handpiece.
Negative pressure or vacuum pump only based systems have the abrasive material pulled through the circuit with the skin acting as a control valve. In vacuum driven systems, a handpiece, which is open on one end, has one line in fluid communication with a source of particles. The particles are usually contained in a mixing bottle. The handpiece has a second line in fluid communication with a source of vacuum. When the open end of the handpiece is placed against the skin (the skin contact area), the opening is closed and the vacuum will draw particle from the mixing bottle into the handpiece, where they will contact the skin. The resulting used particles and abraded skin is then removed through the vacuum line. The handpiece is then moved across the area to be treated. Unfortunately, vacuum only systems, to be effective, must employ relatively high vacuum. High vacuums required for high abrasive flows require significant distortion of the skin, which can lead to bruising. This is especially relevant if larger hand piece orifices (i.e., greater distortion of the skin) are used. The greater the vacuum the more crystal impinges on the skin surface. However, also the more disruption to the underlying dermis. This can actually bruise or result in broken capillaries in sun-damaged or mature skin.
When the two systems are combined the vacuum pump is xe2x80x9cpullingxe2x80x9d the air/crystal through the handpiece while the compressor is xe2x80x9cpushingxe2x80x9d air/crystal through the handpiece. The combined systems provide flexibility by allowing the vacuum levels to be maintained at low levels while allowing the user to adjust the levels of particle velocity by changing the air flow from the compressor. However, in combined systems the activation of the compressor becomes an issue.
The present invention includes a handpiece that has a control line, which allows the user to control the pressure levels present in the working area of the handpiece. The operator""s hands easily operate the control line. In conjunction with the handpiece, the invention includes a pressure sensor for detecting changes in pressure in the working area of the handpiece. The pressure sensor is used in conjunction with switches to activate or deactivate a compressor.
It is an object of the invention to provide a microdermabrasion system where the compressor is activated with the operator""s hand.
It is an object of the invention to provide a pressure sensitive switch for operating a compressor in a MDA system.
It is an object of the invention to provide a MDA system which automatically stops the flow of particles when the working surface is removed form the skin.
It is an object of the invention to provide an MDA handpiece, which can have a large working footprint but still be conformable to hold.